Rangers' Steven Davis tussles with Aiden McGeady after the Celtic winger came off the bench in the 62nd minute at Ibrox. Photograph: Jeff J Mitchell/Getty Images

Celtic's manager, Gordon Strachan, has vehemently denied that a personality clash between himself and Aiden McGeady was responsible for the winger's surprise omission from the starting XI for the Old Firm defeat by Rangers on Saturday.

McGeady and Strachan clashed in spectacular style in December, a row resulting in the Republic of Ireland midfielder being suspended by his club for a fortnight and heavily fined. Despite being a regular in Strachan's side since then, McGeady was dropped for their crucial Scottish Premier League trip to Ibrox, Shaun Maloney taking his place. Given earlier strained relations, that decision by Strachan has prompted further debate over how things stand between player and manager.

Such discussion has clearly irked ­Strachan. "If you look at Aiden's record since he came back from suspension, he has played in most of the games," said the manager, before alluding to the Co-operative Insurance Cup final win over Rangers in March. "When the chips were down, in a cup final when we needed to win, Aiden McGeady was playing. I think that sums it up. If it had ever come down to person­alities, Carlton Palmer would certainly not have played any games for me [at Coventry City]. In fact, there's a lot of players who wouldn't have got a game."

The big question now is whether McGeady will return for the visit of Dundee United to Celtic Park tomorrow night. "I'm not going to explain my tactics," Strachan said when pressed on the exact reason for McGeady being on the bench against Rangers. "I don't stand and say I'm a tactical genius when we win games, and I'm certainly not going to do it when we don't win. If you start talking about tactics then you get into the positives and negatives of the other team, about other players' strengths and weaknesses, and I don't think that is right."

Rangers' 1–0 win took them two points clear in the title race with three games left, although the Celtic defender Gary Caldwell is adamant that his team can still win the championship. "We have two home games to go, two full houses and the real fans can get behind us, carry us over the line and win another championship," the Scotland international said.

"Both halves of the Old Firm have dropped points throughout the season. We are now playing teams in the top half of the table and they are hard fixtures to win so there is still a long way to go, we have to believe that and we do. We still believe we can win it."

Meanwhile, the Scottish Football Association chief executive, Gordon Smith, has welcomed official confirmation from Uefa that Scotland have earned a sixth European place via the Fair Play League. Uefa today published its full table, which puts Scotland in third place behind Norway and Denmark, with all three countries earning an extra spot in Europe.

Motherwell lead St Mirren and Hibernian in the SFA's own fair play table and the top team at the end of the season will take part in the first qualifying round of the new Europa League on 2 July, with the second leg a week later.

The SFA takes into account a range of criteria, including yellow and red cards, crowd behaviour, the actions of club officials and match reports by SPL delegates. Smith said: "It is great news, a tremendous reflection on the game in Scotland. Winning the extra place in Europe shows what fair play can achieve and sends out a strong message to thousands of boys and girls who play football in Scotland.

"We now have six teams representing Scotland in Europe next season, more than ever before. While the recognition is good, it is vitally important that the teams taking part get the right results so we can continue to improve our national coefficient.

"We won't be able to announce who is getting the place until the end of the season," Smith added. "However, we will keep in touch with all the clubs who are in the running so they can at least put provisional plans in place. One thing is for sure, for one ­Scottish club it is going to be a very short close season."

Falkirk have already qualified for the Europa League after reaching the Homecoming Scottish Cup final, while Hearts, Dundee United and Aberdeen are battling for the two spots that are available through the league. Celtic and Rangers will take part in the Champions League, with the SPL champions going straight into the group stages.